The 2070 is fine, and probably the peak of the 'value to FPS' balance at this point. For $650-$700 you're getting GTX 1080 levels of performance which is OK. You'll spank the crap out of games at 1080p, and be pretty damn comfortable at 1440p also.

A 2080 is going to cost you another $350-400 and you'll get around 30% more performance. That's also nice, but it comes at a 40-50% price premium. So yeah if you need the extra grunt it can be justified, but the 2070 is a far better 'value' than the 2080 at this stage. That said, if you can find a cheap 1080Ti used (I did many months ago for around $750), you'd get 2080 performance out of that, just without the ray tracing gubbins.

I think if you spend another $50 on the MSI Gaming Z, which is $695 from same seller, then you will not have any issues. The Gaming Z is built like a tank. IMHO Gigabyte equivalent is also good. Comes down to brand preference. In my experience Gigabyte has been reliable.

Looking for some advice, If I want to be able to play AAA games like assassin's creed at 1440p ~100 fps while also doing some occasional 4K editing, would the 2070 be a suitable gpu upgrade from my 1060?

2070 on the brain. Last night I dreamed I took 2 from a shops display table and sneaked out, got home and installed but couldnt get them to run in SLI. Do want a new setup but my 1060 is enough for my needs.